This Phase I study explores the feasibility by which the technique of dynamic near-infrared optical tomography (DYNOT) can be employed as an accurate, noninvasive tool to assess tissue perfusion of small bowel in neonatal patients at risk for Necrotizing Enterocolitis (NEC). NEC is a disease process that primarily affects premature infants a week to ten days after the initiation of feeding. With a 25% mortality rate, NEC is the most common surgical emergency of newborns. Conservative medical management allows for 60-80% of patients with NEC to resolve spontaneously. However the remaining patients will deteriorate rapidly with a worsening clinical course necessitating surgical intervention. Due to the fact that 90% of patients at risk for NEC are premature infants needing Neonatal- ICU management, more than any other patient population, the surgeon has to be quite careful not to operate on the patients who will resolve, while operating as early as possible on the patients who will not. The experimental plan calls for the evaluation of four specific aims and involves subjects being managed in a Neonatal-ICU environment. The first aim is directed towards implementing a technology development and enhancement effort with the goal of producing more robust numerical methods and to design a near infrared optical tomography device with a neonatal abdominal imaging head. Supplementing this effort will be laboratory studies aimed at identifying the fidelity by which complex physiological signals can be successfully extracted from reconstructed image data. Following optimization of the data collection hardware and numerical methods, we plan to undertake an animal study with the intent to correlate optical tomographic indicators of bowel ischemia to disease staging in the piglet. These studies are intended to evaluate the hypothesis that through quantitative and qualitative imaging the extent of bowel ischemia caused by NEC can be elucidated. From there a clinical study will be done aimed at correlating the optical markers of compromised small bowel tissue perfusion to disease staging and the necessity of surgery. These studies are intended to evaluate the hypothesis that through quantitative and qualitative imaging the two populations of neonatal patients can be differentiated at an early stage, allowing for the precise timing of surgery inherent in treating NEC patients. If successful, the planned studies are expected to identify a range of technology solutions, based on the framework of DYNOT, that are geared towards use in Neonatal-ICU environments. In the long term, it is anticipated that the developed technology will provide a more sensitive and specific approach for the evaluation and management of small bowel perfusion in infants with NEC.